In 1864, Aaron L Dennison and A.O. Bigelow organized the Tremont Watch Company in Boston, Massachusetts. The objective was to produce a "hybrid" movement, leveraging cheap manufacturing in Zurich, Switzerland.
An advertisement published in the March 22, 1893 issue of the Jewelers' Circular and Horological Review supports the fact that Marion Watch Company movements and parts were still being sold.

Early in the history of American watchmaking, the bustling town of Springfield, Massachusetts produced fine watch movements for a nation eager for a new start following the Civil War. For.
While uncommon, the production lines at the watch factories in American were not entirely flawless. Occasionally, we find evidence of movements with errors that were still sold to the market..

Newest Addition to the Digital Archive: Elgin National Watch Co. Price List of Material - No. 3 (1875) Full Online Catalog: https://pocketwatchdatabase.com/guide/company/elgin/catalogs/elgin-national-watch-co.-price-list-material-catalog-1875 In April 1875, the Elgin National Watch Company.
In 1872, the United States Watch Company (Marion) distributed this price list to the trade, detailing the impressive products offered by the company, including their innovative “pendant winders.” At the.